I have a junk 03 SAi v8, I've already swapped the IC to my running 99 non SAI. I'm having problems that seem superlock related with my 99. 3 amigos, stuck in Park, rear windows not working, wipers and flashers don't work. It locks me out every time I disconnect battery luckily the 1515 code works. (Fob does not).
brake and headlights work, along with radio.

I don't want to truly superlock this truck. But thought about swapping ECU and BCU as well since I have the fob from the 03.
I already swapped the upper intake and fuel rail amongst other things. It runs great btw, once I go through the security unlock
Yes, ive tried the hard reset for ecu. It worked once and everything worked, but havent been able to reproduce again after disconnecting batt. Thoughts??

 

I'll apologize now because I don't know a lot about this but I'm very interested to learn. Since the IC and the ECU/BCU are a "team" the source of the problem is going to be related to that mismatch. The only thing I can add is that if you swap in the ECU/BCU there's a chance you'll correct all the weirdness but you'll have a constant SES light due to the non-SAI hardware under the hood, but you're probably aware of that. Obviously the ECU is programmed for a 4.6L and I'm not sure what that mismatch will do but I would love to know. Can I ask what the benefit of the 4.6L intake and rail are? I'm about to due headgaskets on an 02 with a non-SAI 4.0L and I have a 4.6L SAI parts engine too. I was half thinking of swapping the crank and pistons and all the electronics just to get the extra power from the 4.6L, of course that would mean moving the SAI too but I'm not certain of that. Sorry for the quasi-hijack, I'm very interested in what's going on here

 

okay well you did kinda ask a question within a question You can't swap these lower engine parts bc the bore size and crank is going too not match. Some upper parts will match like heads *with mods bc of SAI. Fuel rail and upper intake match. Almost everything pretty much matches above the block from 4.0 to 4.6 minus the mods for SAI. The part numbers are identical with a few exceptions.
Funny you have helped me rethink my original question, thinking that it wouldn't matter with the ecu registration. Of course it will, but is it enough to effect performance on a grand scale? Minor codes don't scare me since my truck is kindve a beater. If it's off a bit in fuel consumption or even light horsepower.....I need to pass state inspection right now

 

BTW I swapped my intake and rail because the other in my 4.0 was in bad shape, especially the fuel rail and injectors. After the swap I had no problems with starting abd idling as I did before. And be careful with the 4.6. My 03 had low miles and looked great, but it had a slipped sleeve. That's why I junked it

 

Lots of confusion here, so lets break it down:

1. By IC I assume you mean instrument cluster - no effect on security although it is matched to BCU via odometer
2. Can be changed by shop with LR Testbook hardware. Runs engine only, no impact on security other than match with BCU
   1. 03 ECU, currently coded as a SAI truck.
   2. 99 ECU, currently codes as a non-sai truck.
3. BCU - controls security, windows, superlock, etc. Changeable/programmable with Nanocom or testbook. Suggest you read here for what can be changed: https://www.nanocom-diagnostics.com/...o-bcu-disco-ii
   1. Controls shift solenoid - programmable
   2. Wipers and flashers - weird. Do they come back after resetting? There are some options in the BCU but not working is not one. Suggest you troubleshoot wiring.
   3. Fob is matched to the BCU, which is matched to the ECU.
   4. ABS - probably separate fault, suggest troubleshooting normal ABS fault. Do you have code reader? This one will read ABS codes:
      Amazon
      Amazon
   5. Superlock controlled by BCU, can be turned off with Nanocom
4. Fuel rail and intake - identical 4.0 to 4.6
5. Engine bits - pistons, rods,, and crank are different 4.6 to 4.0, the rest is identical.
6. Engine programming - slightly different but D2 engine runs closed loop using oxygen sensor 100% of the time if they are functioning, if not it uses the MAF sensor. Either way the ECU adapts fueling to the engine based on readings. ignition timing is identical as far as we know.

 

Thanks both of you. I was under the impression (perhaps mistakenly) that the 4.0 and 4.6 blocks were the same and by nature of swapping the lower end you would increase the displacement to 4.6L. If I'm going this far I would likely swap the electronics across the board as well. And while I don't love SAI, it's benign so as long as the parts are in good shape I would use the SAI heads too. Extinct, in item 2, are you saying SAI can be turned off with a Testbook or is that hardcoded somehow? Is that beyond Nanocom's ability? Thanks again.

 

1. Engine blocks are the same, crank, rods, pistons are different.
2. SAI can be turned off with Testbook, not possible with Nanocom. Alterantively you can swap in a NON-SAI ECU.

 

OK, next crazy question. Assuming I do swap the lower end into the non-SAI 4.0L to create a 4.6L:

1) Ignoring the SAI vs non-SAI, do I need the 4.6L ECU to run the engine properly? Normally I'd assume yes but item 6 above seems to say maybe not. I'm not yet familiar with the version of Motronic that runs the two different engines, but if it's the same then the answer is definitely no.
2) Can Nanocom match the 4.6L ECU to the existing 4.0L BCU and cluster so I don't lose my ODO?3) Can either device reset the ODO in the 4.6L cluster, which would then allow me to simply move all the electronics over from the 2004 to the 2002.

OP, I hope some of these answers are useful to you.

Edit:
This snippet from the BOSCH Motronic 5.2.1 System Overview gives some clarity. In the first section it states that the ECU is used on all Disco V8s and Range Rover P38s below 1999. The next section says that Test Book is needed to change the ECU parameters but the way I'm reading it, the BCU stores the odometer value and the ECU can either read from it, or it can be entered into the ECU manually with Test Book. I guess this is what needs to be done when mixing ECU and BCU so the ODO doesn't blink, but is that telling us that the Nanocom is synching the BCU to the ECU's stored value?

 

Heads are interchangeable, so you can pick SAI or Non-SAI.

BCU is the only part matched to the ODO.

If your state does inspections for Emissions equipment based on VIN you will need the SAI hardware. You might get away with a non-sai ECU/program, depend son how invasive their testing is.

Testbook can basically flash and match anything to anything.

The Nanocom capabiliites can be found on the support section of their site. It can turn off the flashing odo, enable some options, but cannot reflash ecu or bcu.